Transaction

[Error Code: 1101] cadence runtime error Execution failed:
  --> 9a169eb3f3c830a8e3debf4ca5ce9996b390a4ebcda7e7b867f360ddfa4d8d19:80:20
   |
80 |         let item <- self.listing.purchase(
   |                     ^

error: pre-condition failed: listing has already been purchased
   --> 4eb8a10cb9f87357.NFTStorefront:243:16